The Claim

The ratio of low-frequency to high-frequency heart rate variability (LF/HF) increases during psychological stress, reflecting a relative shift toward sympathetic dominance and reduced parasympathetic influence, and is one of the most commonly reported indicators of autonomic imbalance in stress research.

Source: Stress and Heart Rate Variability: A Meta-Analysis and Review of the Literature

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
39score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Description
1 study reviewed
In plain English

When you're stressed, your heart's rhythm changes in a way that shows your body is shifting into 'fight or flight' mode and relaxing less — this change is often used by scientists to measure stress in the body.

See the scientific wording

The ratio of low-frequency to high-frequency heart rate variability (LF/HF) increases during psychological stress, reflecting a relative shift toward sympathetic dominance and reduced parasympathetic influence, and is one of the most commonly reported indicators of autonomic imbalance in stress research.

What the research says

1 study
  1. Study: Stress and Heart Rate Variability: A Meta-Analysis and Review of the Literature

    When people are stressed, their heart rate patterns change in a way that shows their body is in 'fight or flight' mode and not relaxing as much — this study found that’s exactly what happens, and the LF/HF ratio is a reliable way to measure it.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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